1. Field of the Invention
The present invention relates to a printed wiring board, more specifically, to a printed wiring board structured with alternately laminated conductive circuits and insulation layers and having pads on one surface to load electronic components such as an IC.
2. Discussion of the Background
In recent years, as electronic devices become more highly functional, they are also made smaller and thinner. Accordingly, electronic components such as IC chips and LSIs are becoming highly integrated at a rapid pace.
In a printed wiring board manufactured by the method described in Japanese Laid-Open Patent Application 2006-19591, an electrolytic plated layer is formed on a metal foil by electrolytic plating, and the electrolytic plated layer is used as an etching resist to form a conductive circuit by etching. Then, the conductive circuit is used as pads for mounting a semiconductor element.
A printed wiring board manufactured by the method according to Japanese Laid-Open Patent Application H10-41610 has a substrate made of glass epoxy or the like, which causes the printed wiring board to thicken.
The contents of those publications are incorporated herein by reference in their entirety.